Hardly is a confusing word: in modern English, it always means "only a little bit", and is never used as an adverbial form of hard. The adverb corresponding to hard is in fact "hard", as in "He pulled it hard" or "I tried hard", or "They hit him hard".
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Colin FineOct 26 '12 at 11:08

Disagree with last assertion; tightly stretched does not imply “stretched as far as it can go”. Yes, a thing that's tightly stretched might be stretched as far as it can be, but in general more stress gives more strain.
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jwpat7Oct 26 '12 at 0:48

I also disagree that (1) and (2) are good fits for the OP's purpose. "Vigorously stretched" and "harshly stretched" are not commonly used phrases.
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Kristina LopezOct 26 '12 at 1:38

Sorry for the misunderstanding - I was not suggesting "vigorously" or "harshly"; I meant that the OP meant "hardly" for the definitions of "with force" or "in a severe manner" but I was arguing that the use rather implies the 4th definition.
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sacoheOct 26 '12 at 1:54